Fires in confined areas can be extremely difficult to contain much less to extinguish due to a number of factors including, but not limited to, heat buildup, the ready availability of fuel and the presence of toxic gases, all of which make delivery of fire suppressant material difficult. Confined areas include locations such as storage tanks and underground mines as well as below surface fires, such as landfill fires for example. These sites can combine the worst dangers to property and life in that the hot combustion gases are confined and can be prone to explosion and can provide additional fuel to the fire. In addition the combustion gases normally contain toxic levels of carbon monoxide gas, methane gas and other toxic substances. In coal mine fires, for example, the abundance of fuel in a confined, poorly accessible area practically guarantees that the fire will burn for extremely long periods of time with resultant loss of production great property loss. Many coal mines must be abandoned in the event of a fire because of the great difficulty in extinguishing the fire. For example the Jonesville coal mine fire started more than 30 years ago and is still burning. The town of Centrala, Pa. has been abandoned because of a coal mine fire that began in 1961 because of the seeping of noxious gases to the surface. The residents of the City of Youngstown have seen their property values drop to near zero due to the Percy mine fire in Fayette County, Pa. that has been burning for more than 30 years and they are concerned that they will lose their homes.
Although not prone to the extremely long burning periods encountered in coal mine fires, other fire locations such as underground fuel storage tanks, above ground chemical storage tanks and the like present similar problems. It is difficult to apply fire suppressant material to the fire because of the danger to the firefighters from explosion, heat buildup and toxic gases.